I've been using it as my music player on Linux for a few months now. I recently upgraded my home Linux box to Ubuntu 9.04, which in turn forced an upgrade of Amarok from 1.x to 2.x, because Ubuntu has dropped official support for the KDE 3.x runtime libraries (on which Amarok 1.x depends).
This promptly broke Amarok. It started up just fine... but when you hit Play, no sound would come out.
So I enabled the "backports" repository and installed an even later version of Amarok, and that seemed to fix the playback problem. But they've completely rearranged the user interface for no good reason, and they've removed
the graphic EQ, which IMO was one of the features that set it apart from most of the other Linux music players. Not all of us can afford "perfect" headphones or speakers; a graphic EQ is very useful if you need to compensate for deficiencies in the frequency response of your headphones or speakers.
Meh. I guess I'll try it for a few days; if it pisses me off enough, I can always install Foobar2000 under wine.